I have improved during lockdown and I think (sadly) it’s because ice not been running with friends and so talking!
My routes are fairly hilly. I average 5.18 a Km. Sometimes a km on the route is as low as 4,47 a km but then on the steep climbs can be 6.5 a km.
But my average usually about 5.18
Length 6km - 12km
My son... 9 years old average 4.40 on a 5k run and arrives home not having broken a sweat!